Comparison of Recommendations and Use of Cardiovascular Risk Equations by Health Technology Assessment Agencies and Clinical Guidelines.

Objectives: To identify risk equations for cardiovascular diseases (CVDs) in primary and secondary prevention settings that are used or recommended by health technology assessment (HTA) organizations and in clinical guidelines (CGs). Methods: A targeted literature review was conducted using a two-stage search strategy. First, HTA reviews of manufacturers' drug submissions, reports from established HTA organizations (Europe, Canada, and Australia), and CGs from countries with and without HTA organizations, including the United States, were identified. Documents published between September 30, 2006 and September 30, 2016, were examined for cardiovascular risk equations, recommendations, and commentaries. Next, publications associated with risk equations and cited by HTA and CG documents were retrieved. This literature was examined to extract commentaries and risk equation study characteristics. Results: The review identified 47 risk equations, 25 in the primary CVD prevention setting (i.e., patients with no CVD history), including 5 for CVD prevention in diabetes and 22 solely in secondary prevention settings; 11 were identified for heart failure, 3 for stroke or transient ischemic attack, 2 for stable angina, and 11 for acute coronary syndrome or related conditions. A small set of primary prevention equations was found to be commonly used by HTAs, whereas secondary prevention equations were less common in HTA documents. CGs provided more risk equations as options than HTA documents. Conclusions: Although there is an abundance of risk equations developed for primary and secondary prevention, there remains a need for additional research to provide sufficient clinical and HTA guidance for risk estimation, particularly in high-risk or secondary prevention settings.